Centering and locking means for the punches in rivet and forging machines



l `Mlill'2,fl-9 2 6`. v 1,575,461

- s. H. SVENSSON El' AL csn'rnma .um LocxING MEANS Fon 'ras Puncnss 11| anni zum ronGING camas 3 Sheets-Sheet 1 $54. zal l 'March z ,1926. l 1,515,461

S. H. SVENSSON ET AL CENTERING AND LOCKING MEANS FOR THE PUNCHES IN RIVET AND FORGING MACHINES Filed May 8, 1923 I5 Sheets-Sheet 2 Iza/v 61030225 E ven/66 O Zz wz/'6i March 2 1926. 1,575,461

S. H. svENSsoN Er AL CENTERING AND LOCKING MEANS FOR THE PUNCHES IN RIVE AND FORGING MACHINES Filed May 8, 1925 3 SheetS-Sheet- Patented Mar. 2, 1926.

UNITED STATES `PATENT OFFICE;

SVENITG HLMER SVENSSON .AND KARL OSKAR ENGKVIST, QF BOFORS, SWEDEN, AS-

` SIGNORS TO AKTIEBOLAGET BOFORS, OF BOFORS, SWEDEN. i

CENTERING AND LooKiNe MnANsron THE r'UNcHns IN nivn'r AND noname i MACHINES.

Application lfiled May 8,

To all whom it may concern Be it known that we, SVENING HiLMnR SvnNssoN and `KARL OskAii lENcKvisT, subjects of the King ot Sweden, both residing at Botors, Sweden, have invented certain new and useful Improvements in Centering .and Locking Means for the IPunches in Rivet and Forging Machines, of which the following is a specification.

The present invention relates to a unique construction of the centering and locking means tor the punches in rivet and forging machines provided l with two or more punches.

The centering devices as heretofore known and used Suder from the inconvenience of the working pressure loading the punch `shifting device, either wholly or partly, whereby the latter will be subjected to heavy wear. Other known centering devices in use which are not hampered by this drawback command a limited space owing to their being mounted in the main slide proper, and on account of this some of the i parts will be weak, while the centering screws are rendered diilicult of access. As distinguished from these known arrangements, the present invention is so devised that the various parts may be amply dimensioned, besides which the partsconstituting the lock are entirely visible and allow of ready adjustment in the run of the machine.

The invention is illustrated on the accompanying drawings. Fig. 1 is a lateral view, with certain parts shown in section, of an entire machine having three punches, and provided with means constructed according to the present invention. Fig. 2 is a lateral view of a detail of the arrangement as applied to a machine with two punches. Fig. 3 is a plan view of the machine. Fig. 4 is a section on line 4 4 in Fig. 3. Fig. 5 shows a modiiicationin longitudinal section, and Fig. 6 is an end view ot the said ineditication.

5 designates the crank shaft or main shaft ot the machne the crank ot whch is connected in known manner with the main slide 7 by means of the connecting rod 6, the main slide 7 being movable in the longitudinal direction of the machine. rI he lateral guides oi the slide belonging to the trame proper are denoted by 31 (Fig. 4). At the bottom the slide bears on the slide bars 34 which, in

1923.y Serial No. 637,604.

turn, rest on ledges provided on the guides 31 and at the top the slide is guided by the Voverlapping bars 35 attached to the lateral other are two wedge-like projections 13 of hardened steel forming between them a V- shaped slot. The position and the shape of these projections is adapted to the distance between the center lines of the punches and to the wedge-shaped end of the lock bolt 15, which will be described hereinbelow.

Provided in the part 40 of the machine frame, opposite the punches, is a bore hole- 41 having an inclination of about 10o to the horizontal plane, and itted in this bore hole is a bolt housing 14. This bolt housing is in turn provided with a1 bore hole parallel to the horizontal plane, in which latter bore hole the lock bolt 15 is` fitted so as to bemovable therein. This bolt will thus form an angle of'lOo with the line of symmetry of the bolt housing, and it is parallel to the path of movement of the main slide 7. The lock bolt 15 is actuated by an adjustable spring 16 tending to press the same against the punch slide 8. By means of the screw 19 the bolt housing 14 may be displaced in its longitudinal direction Vrelatively to the frame, whereby the bolt 15 is evidently raised or lowered. By suitable means such as a locking screw the bolt housing 14 is locked in the frame in thedesired position.

The die mounted in the frame portion 40 and wherein the blank to be treated, such as a screw blank 4Q, is held in a fixed position opposite the slide 8, is designated by 43.

' The movements of the slide 8 areV stepwise according to the distance between the punches and the action thereof.

At the beginning of the working opera tion the punch 1 and the center line ot the die should bein alignment, that is to say the punch should be on the level indicated by the chain-dotted lines 37 in Fig. 4.

The iirst step in the upsetting operation on the blank is then performed. During the following revolution of the shaft 5, the slide 8 is raised to the position shown in the drawing, that is to say so much that the center line of the punch 2 is brought in alignment with the center line of the blank and the die, and during the next following revolution of the shaft 5 the slide 8l will be further raised so that the punch 3 is f repeated.

These movements of the slide 8 are effected by a punch shifting mechanism operating in the following manner.. vMounted on a secondary lshaft 22 (Figs. 1 and 4) which, in a machine with three punches, has

a speed equal to one third of the speed of the crank shaft 5, is a cam disk 20 provided with a slot 21.' Mounted on a fork 25,

which is guided by a die block 23 on the shaft 22, is a. roller 24 engaging the, slot 21 of the said cam disk 20. The motion thus imparted to the fork by the rotation of the shaft 22 is transmitted through a pivot 26to a lever 27, and further through .a shaft32 and a lever 43 to a roller 12 mounted on astud, said roller 12 running between guides 11 on theslide 8. The cam disk 2() im- `parts a constant unvarying motion to the fork 25, but the position and the movements of the punch slide 8 may be varied by altering the lengths of theleversby displacing the pivot 26 and the stud of the roller 12 through the medium of screws 28 and 33. This punch shifting mechanism is substantially of the same construction as used in certain known machines of the type to which the present invention refers.

When the slide' 8 of the shifting mecha-v nism is moved downwards, so that the punch 1 is `brought in alignment with the die, the lower end of the adjusting screw 1()l is caused to bear on the upper side of the main slide 7. The screw is now adjusted if it does not already occupy a fully adjusted position) lso that the center lines of the punch 1 and the die will be situated on exactly the same straight line. Vhen the main slide 7, andv thus also the slide 8 together with the punch, are now moving downwardly in a direction toward the die, the oblique upper side of the upper lock projection 13 will hit the lower side of the correspondingly shaped oblique lower face of the outer end of the lock bolt, whereby the slide 8 will be securely jammed (locked) against the screw 10. The distance between the said projection 13 and the lock bolt 15 is so adapted that the said locking of the slide 8 will take place before the punch starts working on the blank in the die. On the continued motion of the slide 7 in a. direction toward the die, the lock bolt 15 will be displaced into the housing, thereby oompressing the spring 16,y the pressure of which against the bolt will then keep the .slide 8 securely locked during the upsetting of the screw blank. When the slide 7 moves away from the die, the bolt 15 will evidently return to its initial position under the influence of the spring pressure.

During the next revolution of the main yshaft of the machine, the punch 2 has to be locked in alignment with the blank in the die, that is to say the shifting mechanism will displace the lslide 8 during this revolution in such a manner thatthe punch 2 is brought into the working position. Then the main slide is moving during this revolution toward the die, the locking bolt will be engaged between the two projections 13, before the punch starts working on the blank, the slide 8jbeing thus adjusted and locked by thelocking bolt in the exact position in which the punch is accurately centered with respect tothe die. The adjustment of the locking bolt, so that it will accuratelycenter the other punch, is effected by a displacement of the bolt housing 14, in that the bolt 15 will then be raised or lowered, whereby corresponding raising and lowering of the slide 8 is taking place when the locking bolt 15 is engaged between the projections. f

This adjustment Vwill have no inuence on the centering of the two other punches, such adjustment` only altering the length of the distance along which the oblique surfaces of the locking bolt 15 and the projections'13 slide on each other.

v During the third revolution of the shaft, when the slide of the shifting mechanism is raised so as to bring the punch 3 in alignment with the die, the bottom surface of the lower kprojection 13 will, on the movement of the main slide 7 in a direction toward the die, be caused toI yco-operate with the upper oblique surface of the locking bolt 15, whereby the slide 8 will be pressed against the nut 9 which is mounted on a rod 50 attached to the main slide 7 and extending freely through a bore hole in the slide 8. By adjusting this nut, the locking of th-e punch 3 may thus be effected in an absolutely proper position relatively to the die.

The punch shifting mechanism can and must be so adapted that there will be a clearance of about 2'millimeters for the slide 8 at ythe extreme positions for the different adjustments of the level, so that the very last step of the movement into the extreme position is eifectedby the co-operation of the wedge-shaped locking parts, whereby the A pressure from the shitting mechanism is entirely relieved, and an adjustment may be eliected through the nut 9 and the screws 1() and 19 during the run of the machine, irrespective of the shitting mechanism.

lVhen using only two punches (F 1g. 2), a cam disk is evidently employed, in place of the three-step cam disk 2O used in the embodiment according toFig. 1, which will only adjust the slide on two dilierent levels corresponding to the positions ot the punches 1 and 2 in Fig. 2. The locking of the slide 8 on a. level corresponding to the working position of the punch 1 is etl'ected by a co-operation between the top side ot the .single projection 13 and the bottom side of the wedge-shaped end of the locking bolt, the slide 8 being thus pressed against the screw 10, and the locking of the punch 2 in alignment with the die is effected by a co-operation between the top side of the locking bolt and the bottom side of the projection 13, the slide 8 lbeing thus pressed against the nut 9. a

It is also possible, when punching with only twopunches, to use the slide and the projections shown in Fig. 1, only the threestep cam disk 2O is replaced by a two-step cam disk.

The locking bolt 15 is formed at its rear -end into a boss 49 preventing the bolt from rotating, and an offset 18 on the boss serves as an abutment against a rawhide packing 17, so that no beats will be heard against the bolt housing in machines running at a high rate of speed.

Figs. 5 and 6 show a modification of the arrangement of the locking bolt 15 and the bolt'housing 14.

According to this modification, the locking bolt is inserted in a bore hole in the frame 40, which bore hole is parallel to the direction of movement ot the main slide 7, and the locking bolt is mounted eccentrically in the bolt housing 14, so that the bolt 15 may be raised or lowered by rotating the said housing.

'f desired, the projection or projections 13 may be vertically adjustable instead 01' the bolt 15.

It is also within the scope'ot the invention to arrange the bolt on the slide 8 and the projections on the portion of the frame opposite the slide, but such an arrangement is believed to be less practical.

7hat we claim as new and desire to secure by Letters Patent of the United Statesv of America is 1. In punching machines the combination of a slide, a number of punches mounted on the slide a gate carrying the slide for reciprocating the same in the punching direction, a die for the blank to be punched, a shitting mechanism for giving the slide such an intermittent motion so that the punches in their proper turns are brought in` alignment with the die, means for accurately adjusting and locking the slide 1n each separate Vpunching position, said means consisting ot two lock members, one of these members consisting of a bolt, a housing which does not take part in the adjusting movement ot the slide, said bolt being adjustably fitted in said housing so as to be pressed inwardly in this latter when the slide is moved towards the die, the other lock member being mounted on the slide and means, whereby the lock members are brought out of engagement with each other automatically, only on account ot' the movement ot the gate with the slide rearwardly to a certain degree.

2. In punching machines the combination ot a` slide, a number of punches mounted on the slide, a gate carrying the slide for reciprocating the same in the punching direction, a die for the blank to be punched, a housing for the die provided with a hole, a shitting mechanism tor giving the slide such an intermittent motion so that the punches in their proper turns are brought in alignment with the die, means for accurately adjusting and locking the slide in each separate punching position, said means consisting of two lock members, one of these members consisting of a bolt, a housing which does not take part in the adjusting movement oi' the slide, said bolt being adjustably litted in said housing so as to be pressed inwardly in this latter when the slide is moved towards the die, the other lock member being mounted on the slide and the bolt housing being fitted in the hole of the die housing, said hole having an oblique direction with respect to the direction of the punching operation, whereas the locking bolt is mounted in parallel to the direction of the punching operation so that, on the bolt housing being displaced in the said bore hole, the locking bolt will be adjusted at right-angles to the punching direction.

8. In punching machines the combination ot a slide, a number of punches mounted on the slide, a gate carrying the slide for reciprocating the same in the punching direction, a die for the blank to be punched, a housing ior the die provided with a hole, a shifting mechanism for giving the slide such an intermittent motion so that the punches in their proper turns are brought in alignment with the die, means for accurately adjusting and locking the slide in each separate punching position, said means consisting of two lock members, one of these members consisting of a bolt, another housing, which does not take part in the ad- 1 justing movement ot the slide, said bolt being adjustably fitted in said latter housing so as to be pressed inwardly in this housing when the slide is moved towards the die, the other lock member being mounted on the slide and means, Wherebythe lock members are hroughtout of engagement With each other automatically, only on account of the movement of the gate with the slide rearwardly to a Certain degree, the bolt housing being fitted in the hole of the `die housing, said hole having an oblique direction` with respect to the direction of the punching operation, whereas the locking bolt is mounted in parallely direction of the 10 punching operation so that, on the bolt housing ybeing displaced in the lSaid hole, the locking boltwill he adjusted at right angles to they punching direction.

In testimony whereof we affix our signa- 15 tures.

SVENING HILMER SVENSSN. KARL OSKAR ENGKVIST. 

